package com.rs.adminweb.commons.util;

import java.security.Key;
import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class EncryptDES
{
    private Log log = LogFactory.getLog(this.getClass());
    Key key;

    public EncryptDES(String str)
    {
        setKey(str);// 生成密匙
    }

    public EncryptDES()
    {
        setKey("siyue_qi");
    }

    /**
     * 根据参数生成KEY
     */
    public void setKey(String strKey)
    {
        try
        {
            KeyGenerator _generator = KeyGenerator.getInstance("DES");
            _generator.init(new SecureRandom(strKey.getBytes()));
            this.key = _generator.generateKey();
            _generator = null;
        }
        catch (Exception e)
        {
            throw new RuntimeException("Error initializing SqlMap class. Cause:" + e);
        }
    }

    /**
     * 加密String明文输入,String密文输出
     */
    public String getEncString(String strMing)
    {
        byte[] byteMi = null;
        byte[] byteMing = null;
        String strMi = "";
        BASE64Encoder base64en = new BASE64Encoder();
        try
        {
            byteMing = strMing.getBytes();
            byteMi = this.getEncCode(byteMing);
            strMi = base64en.encode(byteMi);
        }
        catch (Exception e)
        {
            throw new RuntimeException("Error initializing SqlMap class. Cause:" + e);
        }
        finally
        {
            base64en = null;
            byteMing = null;
            byteMi = null;
        }
        return strMi;
    }

    /**
     * 解密 以String密文输入,String明文输出
     * 
     * @param strMi
     * @return
     */
    public String getDesString(String strMi)
    {
        BASE64Decoder base64De = new BASE64Decoder();
        byte[] byteMing = null;
        byte[] byteMi = null;
        String strMing = "";
        try
        {
            byteMi = base64De.decodeBuffer(strMi);
            byteMing = this.getDesCode(byteMi);
            strMing = new String(byteMing, "UTF8");
        }
        catch (Exception e)
        {
            throw new RuntimeException("Error initializing SqlMap class. Cause:" + e);
        }
        finally
        {
            base64De = null;
            byteMing = null;
            byteMi = null;
        }
        return strMing;
    }

    /**
     * 加密以byte[]明文输入,byte[]密文输出
     * 
     * @param byteS
     * @return
     */
    private byte[] getEncCode(byte[] byteS)
    {
        byte[] byteFina = null;
        Cipher cipher;
        try
        {
            cipher = Cipher.getInstance("DES");
            cipher.init(Cipher.ENCRYPT_MODE, key);
            byteFina = cipher.doFinal(byteS);
        }
        catch (Exception e)
        {
            throw new RuntimeException("Error initializing SqlMap class. Cause:" + e);
        }
        finally
        {
            cipher = null;
        }
        return byteFina;
    }

    /**
     * 解密以byte[]密文输入,以byte[]明文输出
     * 
     * @param byteD
     * @return
     */
    private byte[] getDesCode(byte[] byteD)
    {
        Cipher cipher;
        byte[] byteFina = null;
        try
        {
            cipher = Cipher.getInstance("DES");
            cipher.init(Cipher.DECRYPT_MODE, key);
            byteFina = cipher.doFinal(byteD);
        }
        catch (Exception e)
        {
            throw new RuntimeException("Error initializing SqlMap class. Cause:" + e);
        }
        finally
        {
            cipher = null;
        }
        return byteFina;
    }

    public static void main(String[] args)
    {
        EncryptDES des = new EncryptDES();
        // 设置密钥
        // des.setKey("12345678");

        String str1 = "";
        // DES加密
        String str2 = des.getEncString(str1);
        String deStr = des.getDesString("pn0sA2/J888=");
        System.out.println("密文:" + str2);
        // DES解密
        System.out.println("明文:" + deStr);
    }

}
